/**
 * <copyright>
 * Copyright (c) 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 * </copyright>
 *
 */
package org.eclipse.bpel.model.impl;

import java.util.Collection;

import org.eclipse.bpel.model.Activity;
import org.eclipse.bpel.model.ExtensibleElement;
import org.eclipse.bpel.model.ModelPackage;
import org.eclipse.bpel.model.ModelPackage;
import org.eclipse.bpel.model.Sequence;
import org.eclipse.bpel.model.util.ReconciliationHelper;
import org.eclipse.emf.common.notify.NotificationChain;
import org.eclipse.emf.common.util.EList;
import org.eclipse.emf.ecore.EClass;
import org.eclipse.emf.ecore.EReference;
import org.eclipse.emf.ecore.InternalEObject;
import org.eclipse.emf.ecore.util.EObjectContainmentEList;
import org.eclipse.emf.ecore.util.InternalEList;

/**
 * <!-- begin-user-doc -->
 * An implementation of the model object '<em><b>Sequence</b></em>'.
 * <!-- end-user-doc -->
 * <p>
 * The following features are implemented:
 * <ul>
 *   <li>{@link org.eclipse.bpel.model.impl.SequenceImpl#getActivities <em>Activities</em>}</li>
 * </ul>
 * </p>
 *
 * @generated
 */
public class SequenceImpl extends ActivityImpl implements Sequence {
	/**
	 * The cached value of the '{@link #getActivities() <em>Activities</em>}' containment reference list.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @see #getActivities()
	 * @generated
	 * @ordered
	 */
	protected EList<Activity> activities;

	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	protected SequenceImpl() {
		super();
	}

	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated NOT
	 */
	@Override
	protected EClass eStaticClass() {
//		return ModelPackage.Literals.SEQUENCE;
		return ModelPackage.Literals.SEQUENCE;
	}

	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	public EList<Activity> getActivities() {
		if (activities == null) {
			activities = new EObjectContainmentEList<Activity>(Activity.class, this, ModelPackage.SEQUENCE__ACTIVITIES);
		}
		return activities;
	}

	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	@Override
	public NotificationChain eInverseRemove(InternalEObject otherEnd,
			int featureID, NotificationChain msgs) {
		switch (featureID) {
			case ModelPackage.SEQUENCE__ACTIVITIES:
				return ((InternalEList<?>)getActivities()).basicRemove(otherEnd, msgs);
		}
		return super.eInverseRemove(otherEnd, featureID, msgs);
	}

	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	@Override
	public Object eGet(int featureID, boolean resolve, boolean coreType) {
		switch (featureID) {
			case ModelPackage.SEQUENCE__ACTIVITIES:
				return getActivities();
		}
		return super.eGet(featureID, resolve, coreType);
	}

	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	@SuppressWarnings("unchecked")
	@Override
	public void eSet(int featureID, Object newValue) {
		switch (featureID) {
			case ModelPackage.SEQUENCE__ACTIVITIES:
				getActivities().clear();
				getActivities().addAll((Collection<? extends Activity>)newValue);
				return;
		}
		super.eSet(featureID, newValue);
	}

	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	@Override
	public void eUnset(int featureID) {
		switch (featureID) {
			case ModelPackage.SEQUENCE__ACTIVITIES:
				getActivities().clear();
				return;
		}
		super.eUnset(featureID);
	}

	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	@Override
	public boolean eIsSet(int featureID) {
		switch (featureID) {
			case ModelPackage.SEQUENCE__ACTIVITIES:
				return activities != null && !activities.isEmpty();
		}
		return super.eIsSet(featureID);
	}

	@Override
	protected void adoptContent(EReference reference, Object object) {
		if (object instanceof Activity) {
			ReconciliationHelper.adoptChild(this, activities,
					(Activity) object, "ACTIVITY");
		}
		super.adoptContent(reference, object);

	}

	@Override
	protected void orphanContent(EReference reference, Object obj) {
		if (obj instanceof Activity) {
			ReconciliationHelper.orphanChild(this, (Activity) obj);
		}
		super.orphanContent(reference, obj);
	}

	/**
	 * Given an element and a sequence, returns the predecessor activity
	 * of the element in the sequence.
	 * 
	 * If the element is not contained in the sequence, null is returned.
	 * If the element is the first activity in the sequence and hence has
	 * no predecessor, null is returned
	 */
	@Override
	public ExtensibleElement findPredecessor(ExtensibleElement element) {
		EList<Activity> seqActivities = getActivities();
		if (seqActivities.isEmpty()) {
			return null;
		}
		
		Activity predecessor = null;
		for (Activity act : seqActivities) {
			if (element.equals(act)) {
				return predecessor;
			}
			predecessor = act;
		}
		
		return null;
	}

	@Override
	public ExtensibleElement findSuccessor(ExtensibleElement element) {
		EList<Activity> seqActivities = getActivities();
		if (seqActivities.isEmpty()) {
			return null;
		}
		
		boolean stop = false;
		for (Activity act : seqActivities) {
			
			if (stop) {
				return act;
			}
			
			if (element.equals(act)) {
				stop = true;
				continue;
			}
		}
		
		return null;
	}

	@Override
	public ExtensibleElement getLastActivity() {
		if (null == activities) {
			return null;
		}
		
		if (0 == activities.size()) {
			return null;
		}
			
		return activities.get(activities.size() -1);
	}
	
} //SequenceImpl
